Active immunotherapy to treat human cancer is one of the most rapidly developing fields in oncology. The Immune Monitoring Core Laboratory was established as a resource for investigators needing to monitor immunotherapy trials. The IMCL occupies 700 sq ft lab space with two adjacent 100 sq ft cell culture rooms in the new Center for Immunology Research (CCIR) facility. Created as a state-of-the-art facility, the goal of the lab is to work closely with each investigator at all stages of the clinical trial process by planning both the types of immune monitoring assays and number of data points suitable for each particular clinical trial, processing specimens, performing assays, and providing help with data interpretation. The IMCL also allows researchers to use dedicated equipment not usually available in individual labs. As part of this commitment to offer the most recent technology in immune monitoring to all researchers, the IMCL teams with industry and academic collaborators to develop new assays, to validate immune assays and to set rigorous quality control standards. The techniques used by the IMCL for immune monitoring include 1) cytokine ELISPOT assays; 2) 6-color FACS phenotyping assays using HLA class I and class II peptide tetramers/multimers; 3) intracellular cytokine staining methods; 4) advanced ELISA-based technology that measures multiple cytokines in a single sample or reaction (multiplex cytokine analysis); 5) newer T-cell proliferation assays using CFSE labeling coupled to FACS; 6) more sensitive non-radioactive methods to determine antigenspecific CTL activity using FACS. The IMCL plays a key role in clinical trial development. During the previous funding period, IMCL services were used by 10 investigators from 8 of the 19 CCSG programs. 90 % of users had peer-reviewed funding and accounted for 80.7 % of utilization. Future plans are focused on Increasing the IMCL participation in CCSG-related clinical studies, as well as developing new assays to improve the amount and quality of information that can be obtained from a clinical trial.